1959年来中国天山冰川资源时空变化

基于两期冰川编目数据与气象数据,对天山1959年来冰川资源的时空变化特征进行研究。研究发现：① 天山地区现有冰川7934条,面积7179.77 km²,冰储量756.48 km³。冰川数量以面积< 1 km²的冰川居多,面积以1~10 km²和≥ 20 km²的冰川为主,冰川集中分布在海拔3800~4800 m之间。② 在四级流域中,阿克苏河流域冰川面积最大为1721.75 km²,面积最小的是伊吾河流域,为56.03 km²。在各市（州）中,阿克苏地区冰川资源量最多,其面积和储量分别占天山总量的43.28%和68.85%;冰川资源量最少的市（州）是吐鲁番地区,面积和储量仅占天山总量的0.23%和0.07%。③ 1959年来,天山地区冰川面积减少了1619.82 km²（-18.41%）,储量亏损了104.78 km³（-12.16%）,其中数量以< 1 km²的冰川减少最多,面积减少以< 5 km²的冰川最为严重。④ 冰川变化呈现明显的区域差异,变化速度最快的是天山东段博格达北坡流域,变化最慢的是中部的渭干河流域。初步分析认为夏季气温显著上升带来的消融大于年内降水带来的积累是天山冰川退缩的主要原因。

Spatial-temporal variation of glacier resources in ChineseTianshan Mountains since 1959

Based on the glacier inventories and meteorological data, spatial-temporal variations of glaciers in Chinese Tianshan Mountains were analyzed systematically. The results show that: (1) 7934 glaciers with an area of 7179.77 km² and volume of 756.48 km³ were identified in the study area. The number of glaciers below 1 km² accounts for the majority part of glaciers in the Chinese Tianshan Mountains. In contrast, glaciers between 1 to 10 km² and larger than 20 km² have the largest proportions of the total glacier surface area. The glaciers in the study area are mainly distributed at elevations of 3800-4800 m. (2) In 10 watersheds, the Akesu River Basin contains the most of the glaciers with a surface area of 1721.75 km², but the Yiwu River Basin has the least glaciers whose surface area is 56.03 km². There is an obvious difference of glaciers in different regions. In the Akesu region, glacier resource is the most abundant, which accounts for 43.28% and 68.85% in total surface area and volume. In the Turpan region, glacier resource is the least, which accounts for only 0.23% and 0.07% of the total surface area and volume in this region. (3) In the past half century, the loss in glacier area and ice volume were 1619.85 km² (-18.64%) and 104 km³ (21.63%), respectively. Glaciers smaller than 1.0 km² constituted the main body of the decreased glacier number. Glaciers below 5 km² experienced a significant recession. (4) The relative rates of area change for these glaciers were different for different drainage basins. The fastest change of glacier area occurred on the northern slope of the Bogda Basin and the lowest appeared in the Weigan River Basin. The main reason for glacier retreat in this region was that glacier melting caused by rising summer temperatures is greater than glacier mass supply by increased precipitation during the study period.